In the fabrication of various structures it is often necessary to hold pieces in a cross shaped relationship for gluing, welding, nailing, etc. This is difficult with conventional vices, grippers and clamps because the angular relationship is seldom prefectly achieved. For example, in the construction of T spars and cross shaped spars for model airplane construction there is a common problem of holding the webs accurately while they are fastened together by gluing or welding.